摘要：In order to study the change law of load sharing ratio of composite foundation with long-short piles,the behavior of load sharing ratio was studied on the basis of laboratory tests,in which the pile spacing,cushion thickness,long pile length,short pile length,long pile modulus and short pile modulus were taken into account.Conclusions are as follows:With the decrement of pile spacing,the load sharing ratio of long and short piles became larger while that of soil became smaller.It was not economical by reducing the pile spacing to improve the load sharing ratio of long pile; With increasing thickness of cushion,the load sharing ratio of long piles became smaller,the load sharing ratio of soil became larger while that of short piles changed little.Setting a cushion significantly improved the pile and soil load sharing allocation; With increasing length of long piles,the load sharing ratio of long piles became larger,the load sharing ratio of soil became smaller while that of short piles changed little.Increasing long pile length improved,to some extent,the long pile load sharing ratio; Short piles length had little effect on load sharing ratio;With increasing long pile modulus,the load sharing ratio of long piles became larger,the load sharing ratio of soil became smaller while that of short piles changed little.Increasing the length of long pile modulus significantly improved the long pile load sharing ratio; With increasing short pile modulus,the load sharing ratio of long piles became smaller while that of short piles and soil became larger.Increasing short-pile modulus had a certain influence on load sharing ratio distribution.%為了研究長短樁復合地基豎向荷載分擔比的變化規律,在室內模型試驗的基礎上,對不同樁間距、墊層厚度、長樁長度、短樁長度、長樁模量和短樁模量等情況下長短樁復合地基荷載分擔比的變化性狀進行了分析.結果表明,隨樁間距的減小,長樁和短樁的荷栽分擔比均增大,樁間土的荷栽分擔比減小,通過減小樁間距來提高長樁荷載分擔比是不經濟的；隨墊層厚度的增加,長樁的荷栽分擔比減小,樁間土的荷載分擔比增大,短樁的荷載分擔比變化較小,墊層的設置能明顯改善樁、土荷載分擔的分配；隨長樁長度的增加,長樁的荷載分擔比增大,樁間土的荷載分擔比減小,短樁的荷載分擔比變化較小,增加長樁長度能一定程度提高長樁荷栽分擔比；短樁長度對荷栽分擔比的影響較小；隨長樁模量的增大,長樁的荷栽分擔比增大,樁間土的荷栽分擔比減小,短樁的荷栽分擔比變化較小,增加長樁模量能顯著提高長樁荷載分擔比；隨短樁模量的增大,長樁的荷栽分擔比減小,短樁和樁間土荷載分擔比均增大,增加短樁模量對荷載分擔比分配有一定影響.
